I'm trying to get my head around i18n with Catalyst. As far as I understood the matter, there are two ways to make translations with Perl: Maketext and Gettext. However, I have a requirement to support gettext's .po format so basically I'm going with gettext.
Now, I've found Catalyst::Plugin::I18n and thus Locale::Maketext::Lexicon, which does what I want most of the time. However, it doesn't generate proper pluralization forms, i.e. properly writing msgid_plural and msgstr[x] into the .pot file. This happens probably because Maketext depends on its bracket notation [quant,_1...] and thus has to have the same notation in the translation.
Yet another solution might be using some direct gettext port like Locale::Messages, however this would mean rewriting C::P::I18n.
Does anybody have a proper solution for this problem apart from rewriting several modules? Anything that combines proper gettext with all its features and Catalyst will do.
You will probably get a better answer on the mailing list:
http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/catalyst
I assume you've also read this:
http://www.catalystframework.org/calendar/2006/18
Related
I'd like to check hardcoded values in (a lot of) Smartforms and SAPScript forms.
I have found a way to read the source code of both of these, but it seems that i will have to go through a lot of parsing before I get anything reliable.
I've come across function module GET_LITERAL but that doesn't seem to help me much since i have to specify the offset of the value, if i got right what the function is doing in the first place.
I also found RS_LITERAL_LIST but that also doesn't do what i expect.
I also tried searching for reports and methods, but haven't found anything that seemed to help.
A backup plan would be to get some good parsing tool, so do you know of anything like that.
Anyway, any hints would be helpful and appreciated.
[EDIT]
Forgot to mention, the version of my system is 4.6C
If you have a fairly recent version of ABAP, you can use a regex.
Follow the pattern of this example, but use your source as the text and create your own regex. Have it look for any single quotes on the end of a word separated by spaces or any integers with spaces on either side. That's just a start, you might need to work on a better pattern.
String functions count, find, and match
I'm currently working on a project for which I think being able to come up with phonetic representations of words in various languages would be really helpful. I know Aspell does this pretty well, but I don't think there's a very easy way to get at their phonetic representations, so I ask: is there some other good package for getting the phonetic representation of a word given the word and the language/dialect/accent/whatever it's coming from?
This doesn't need to be in any particular language, but if it were Perl, that would be best.
I've already tried Soundex, Metaphone, DoubleMetaphone, and everything else in Text::Phonetic, and none of that stuff was very good – definitely nowhere near as good as the stuff in Aspell.
The first thing that springs to mind is Soundex. Of course, there is a Perl module Soundex, too. While this is designed to generate a soundex "key" from input it might be useful in mapping different variants to a common key.
There is a package Text::Aspell in CPAN. Might be useful.
I you are trying to make a google style suggestion/correction system, it's not based on just phonetics or AI, but on a massive amount of user input. When a user makes a search, and doesn't click in any link but corrects the input and searches again, it gives google a lot of data about "correct" writing than a phonetics test or dictionary matching.
The main problem is in human language itself, it's not that people speak or write in a deterministic way, let alone in multiple languages.
Of course , i might be wrong, but if you need a library that let's you do this:
getLanguage(string);
I want to see that working, really.
Something I keep doing is removing comments from a file as I process it. I was was wondering if there a module to do this.
Sort of code I keep writing time and again is
while(<>) {
s/#.*// ;
next if /^ \s+ $/x ;
**** do something useful here ****
}
Edit Just to clarify, the input is not Perl. It is a text file of my own making that might have data I want to process in some way or other. I want to beable to place comments that are ignored by my programs
Unless this is a learning experience I suggest you use Regexp::Common::comment instead of writing your own regular expressions.
It supports quite a few languages.
The question does not make clear what type of file it is. Are we dealing with perl source files? If so, your approach is not entirely correct - see gbacon's comment. Perl source files are notoriously difficult (impossible?) to parse with regex. In that case, or if you need to deal with several types of files, use Regexp::Common::comment as suggested by Niffle. Otherwise, if you think your regex logic is correct for your scenario, then I personally prefer to write it explicitly, it's just a pair of strighforward lines, there is little to be gained by using a module (and you introduce a dependency).
It is "common knowledge" that source filters are bad and should not be used in production code.
When answering a a similar, but more specific question I couldn't find any good references that explain clearly why filters are bad and when they can be safely used. I think now is time to create one.
Why are source filters bad?
When is it OK to use a source filter?
Why source filters are bad:
Nothing but perl can parse Perl. (Source filters are fragile.)
When a source filter breaks pretty much anything can happen. (They can introduce subtle and very hard to find bugs.)
Source filters can break tools that work with source code. (PPI, refactoring, static analysis, etc.)
Source filters are mutually exclusive. (You can't use more than one at a time -- unless you're psychotic).
When they're okay:
You're experimenting.
You're writing throw-away code.
Your name is Damian and you must be allowed to program in latin.
You're programming in Perl 6.
Only perl can parse Perl (see this example):
#result = (dothis $foo, $bar);
# Which of the following is it equivalent to?
#result = (dothis($foo), $bar);
#result = dothis($foo, $bar);
This kind of ambiguity makes it very hard to write source filters that always succeed and do the right thing. When things go wrong, debugging is awkward.
After crashing and burning a few times, I have developed the superstitious approach of never trying to write another source filter.
I do occasionally use Smart::Comments for debugging, though. When I do, I load the module on the command line:
$ perl -MSmart::Comments test.pl
so as to avoid any chance that it might remain enabled in production code.
See also: Perl Cannot Be Parsed: A Formal Proof
I don't like source filters because you can't tell what code is going to do just by reading it. Additionally, things that look like they aren't executable, such as comments, might magically be executable with the filter. You (or more likely your coworkers) could delete what you think isn't important and break things.
Having said that, if you are implementing your own little language that you want to turn into Perl, source filters might be the right tool. However, just don't call it Perl. :)
It's worth mentioning that Devel::Declare keywords (and starting with Perl 5.11.2, pluggable keywords) aren't source filters, and don't run afoul of the "only perl can parse Perl" problem. This is because they're run by the perl parser itself, they take what they need from the input, and then they return control to the very same parser.
For example, when you declare a method in MooseX::Declare like this:
method frob ($bubble, $bobble does coerce) {
... # complicated code
}
The word "method" invokes the method keyword parser, which uses its own grammar to get the method name and parse the method signature (which isn't Perl, but it doesn't need to be -- it just needs to be well-defined). Then it leaves perl to parse the method body as the body of a sub. Anything anywhere in your code that isn't between the word "method" and the end of a method signature doesn't get seen by the method parser at all, so it can't break your code, no matter how tricky you get.
The problem I see is the same problem you encounter with any C/C++ macro more complex than defining a constant: It degrades your ability to understand what the code is doing by looking at it, because you're not looking at the code that actually executes.
In theory, a source filter is no more dangerous than any other module, since you could easily write a module that redefines builtins or other constructs in "unexpected" ways. In practice however, it is quite hard to write a source filter in a way where you can prove that its not going to make a mistake. I tried my hand at writing a source filter that implements the perl6 feed operators in perl5 (Perl6::Feeds on cpan). You can take a look at the regular expressions to see the acrobatics required to simply figure out the boundaries of expression scope. While the filter works, and provides a test bed to experiment with feeds, I wouldn't consider using it in a production environment without many many more hours of testing.
Filter::Simple certainly comes in handy by dealing with 'the gory details of parsing quoted constructs', so I would be wary of any source filter that doesn't start there.
In all, it really depends on the filter you are using, and how broad a scope it tries to match against. If it is something simple like a c macro, then its "probably" ok, but if its something complicated then its a judgement call. I personally can't wait to play around with perl6's macro system. Finally lisp wont have anything on perl :-)
There is a nice example here that shows in what trouble you can get with source filters.
http://shadow.cat/blog/matt-s-trout/show-us-the-whole-code/
They used a module called Switch, which is based on source filters. And because of that, they were unable to find the source of an error message for days.
How do can I create binary trees in Perl?
CPAN contains a very wide variety of different modules, and rather than reinventing the wheel, I would suggest looking for it there first. Tree::Binary seems to do what you want to do.
I'm guessing this is some kind of homework assignment (although it's hard to tell from the question), so if you actually have to write your own, a good place to start would be learning how to create objects in Perl (here's a tutorial). The wikipedia page will probably be helpful as well.
A more detailed question will yield better responses.
There's the Tree::Binary module in CPAN...
Although I haven't used it, Tree::RedBlack creates the tree and keeps it balanced (if doing deletes or insertions). If I recall, some of the other tree modules may not provide this capacity (if I have it right).
Chris
I would avoid Tree::Binary from CPAN. We have production software that depends on it, and its API has changed significantly twice in the past two years, making the system crash. For instance, there is a function that continues to do the same thing, but the authors saw fit to at first call it "set_left", then change it to "left", and now "setLeft".